RF Noise Generator

Design

• Useful as a filter test signal source
• From Experimental Methods in RF Design
  • Fig 7.72
  • Described as "not flat"
• "Junk box" parts
  • (2) 2N3904 transistors
  • (2) 5V (nominal) zener diodes
• Noise figure -50 dBm @ 10 MHz

Schematic

Prototype

• Unique nodes in red
• Prototype on single sided copper clad PCB
• KiCAD zener packages have backwards silkscreen (will need to fix on OshPark PCBs)

Meaurements

• Background noise
• Generator off
• Average ~ -64 dB

• Noise Generator On
• Falls off with frequency, but better than -50 dB

Assembly Sheet

RF Noise Generator Rev 1